VMS Help
PASCAL, Attributes, KEY, Options
*Conan The Librarian (sorry for the slow response - running on an old VAX)
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You can specify certain characteristics of the record key by
listing the desired options on the KEY attribute. With these
options, you can control the order of the collating sequence and
you can allow changes or duplicates on a key.
See the "Compaq Pascal Language Reference Manual" for the
complete description of using these options.
This option, along with DESCENDING, allows you to specify the
collating sequence for the key field. By default, the primary
key and alternate key are ASCENDING.
When creating a new file, Pascal will create the key with the
collating order specified. When opening an existing file, the
Run-Time Library will verify that the existing key matches the
collating order specified. If neither ASCENDING or DESCENDING
is specified when opening an existing file, both types will be
accepted.
This option allows you to specify that changes can be performed
on the key.
The default for the primary key is NOCHANGES and the default for
alternate keys is CHANGES. You can override the CHANGES on
alternate keys with NOCHANGES. It is illegal to specify CHANGES
on the primary key.
When opening an existing file, the Pascal Run-Time Library
ignores this option.
3 - DESCENDING(see ASCENDING)
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This option allows you to specify that duplicates of the key are
allowed.
The default for the primary key is NODUPLICATES and the default
for alternate keys is DUPLICATES.
When opening an existing file, the Pascal Run-Time Library
ignores this option.
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